JP2001178979A - Rotating hook device for sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotating hook device for a sewing machine which can be rotated oilless at a high speed for a long period of time. SOLUTION: At least either of the sliding surfaces of an rotating hook bobbin case holder 4 and rotating hook 3 of the rotating hook device of the sewing machine having the rotating hook bobbin case holder 4 capable of housing a bobbin 8 and the rotating hook 3 capable of housing this rotating hook bobbin case holder 4 is coated with a coating layer 12 consisting of carbide carbon and the other is coated with a resin layer 13 consisting of a polyimide resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotary hook device for a sewing machine, and more particularly to a rotary hook device for a sewing machine suitable for an industrial sewing machine that rotates at a high speed.

[0002]

2. Description of the Related Art In general, a conventional rotary hook device of a sewing machine includes:
It has an inner hook that can store the bobbin and an outer hook that can store the inner hook. The inner hook is formed by engaging a hook stopper member provided on the sewing machine body with a detent for rotation prevention formed in the inner hook. The shuttle is stopped and the outer shuttle is rotationally driven.

[0003] A conventional rotary hook device of a sewing machine is generally formed of a steel material. Therefore, a sliding surface, for example, a rail of the inner hook and an outer hook to which the rail of the inner hook fits. Has a large coefficient of friction with the rail groove. And, due to the large friction coefficient between the rail and the groove, a large pressing force is generated on the inner surface of the hook member for preventing rotation of the inner hook and the concave portion of the inner hook on which the hook member is fitted. ,as a result,
It is known that the upper thread cannot be pulled out smoothly, the tension of the upper thread changes, the quality of sewing products deteriorates, and the sliding surface wears.

As one means for solving such a problem, there has been proposed a rotary hook device of a sewing machine configured to supply a lubricating oil to a sliding surface. And the like may be stained by the lubricating oil, and there is a problem that the quality of the sewn product cannot always be properly maintained.

Therefore, as another means for solving the above-mentioned problems, there has been proposed a rotary hook device of a sewing machine which can be used in an oilless state. Examples of this type of rotary hook device include a device in which a sliding surface is coated with a high-density polyethylene resin containing a lubricant, and a device in which the sliding surface is hard such as DLC (diamond-like carbon) or a carbon hard film. Which have been coated with a coating layer of (1).

[0006]

By the way, in recent sewing machines, especially industrial sewing machines which rotate at high speed, the needle reciprocates up to 5,000 times per minute and the shuttle rotates up to 10,000 times per minute. In such a high-speed rotating sewing machine, the conventional configuration in which the sliding surface is covered with a resin containing a lubricating oil or a hard coating layer as described above has insufficient durability without lubrication and has a long There has been a problem that high-speed rotation cannot be performed without lubrication over a period.

[0007] A hard coating layer such as DLC has improved wear resistance and friction resistance, but has a hardness of about Hv3000, which is easily broken, and has a high load-bearing property and a high resistance to the base material. A phenomenon occurs in which the adhesion is inferior, and the other sliding surface that comes into contact is polished.

The present invention has been made in view of these points, and an object of the present invention is to provide a rotary hook device of a sewing machine that can be rotated at high speed without lubrication for a long period of time.

[0009]

In order to achieve the above-mentioned object, a rotary hook device of a sewing machine according to the present invention according to claim 1 is characterized in that at least a sliding surface between an inner hook and an outer hook is provided. One is covered with a coating layer made of carbide and carbon, and the other is covered with a resin layer made of a polyimide resin. And, by adopting such a configuration, the sliding surface formed by the coating layer has a low coefficient of friction, self-lubricating property, large load resistance and adhesion, and the other sliding surface in contact with the sliding surface. There is no occurrence of the phenomenon of polishing. Furthermore, since the sliding surface formed of the resin layer has excellent heat resistance, it is possible to prevent thermal deformation due to heat generated by sliding resistance. Therefore,
It can be rotated at high speed without lubrication for a long time.

A second aspect of the present invention is characterized in that the sliding surface of the inner hook is formed by a coating layer, and the outer hook is formed by a resin layer made of a polyimide resin. And by adopting such a configuration,
It is possible to easily obtain excellent durability without lubrication on the sliding surface where the inner and outer hooks are in contact with each other, and to easily reduce the weight of the outer hook, so that the stress on the sliding surface can be reduced. And a more excellent durability without lubrication can be obtained.

A third feature of the rotary hook device for a sewing machine according to the present invention is that the resin layer contains an additive.
And by adopting such a configuration, the wear resistance and mechanical strength of the resin layer can be easily improved.

A fourth feature of the present invention is that the additive contains at least one of carbon fiber, graphite, molybdenum disulfide and fluororesin. By adopting such a configuration, it is possible to easily improve the self-lubricating property of the resin layer and reduce the friction coefficient.

A fifth aspect of the present invention is characterized in that the resin layer contains 1 to 30% by weight of a lubricant. By adopting such a configuration, it is possible to easily improve the self-lubricating property of the resin layer and reduce the friction coefficient.

A feature of the rotary hook device of the sewing machine according to the present invention is that at least the sliding surfaces of the inner hook and the outer hook are covered with a coating layer made of carbide and carbon. And by adopting such a configuration, the sliding surface formed by the coating layer has a low coefficient of friction,
Since it has self-lubricating properties, large load resistance and adhesion, and does not cause the phenomenon of polishing the other sliding surface to be in contact with, it can be rotated at high speed without lubrication for a long period of time.

A feature of the rotary hook device for a sewing machine according to the present invention according to claim 7 is that the outer hook is formed in a predetermined shape from a material lighter than steel. By adopting such a configuration, the outer hook can be easily reduced in weight, the stress on the sliding surface can be reduced, and further excellent durability without lubrication can be obtained.

The feature of the rotary hook device of the sewing machine according to the present invention is that the outer hook is formed by covering the surface of a base formed into a predetermined shape with aluminum or an aluminum alloy with an intermediate film made of chromium. There is in the point. By adopting such a configuration, it is possible to reduce the weight of the outer kettle, and to strengthen the surface of the base material to prevent the outer kettle from being damaged.

A ninth aspect of the present invention is characterized in that the intermediate film has a thickness of 1 to 10 μm. And by adopting such a configuration, it is possible to more reliably prevent the outer hook from being damaged.

According to a tenth aspect of the present invention, a rotary hook device for a sewing machine according to the present invention is characterized in that an outer hook is formed by covering the surface of a base formed of aluminum or an aluminum alloy into a predetermined shape with an intermediate film made of a nickel alloy. It is in the point. By employing such a configuration, the outer kettle can be reduced in weight, and the surface of the base can be strengthened to prevent the outer kettle from being damaged.

The eleventh aspect of the rotary hook device for a sewing machine according to the present invention is that the intermediate film has a thickness of 1 to 15 μm. And by adopting such a configuration,
It is possible to more reliably prevent the outer hook from being damaged.

A twelfth aspect of the present invention is characterized in that at least the outer peripheral surface of the bobbin is covered with a coating layer made of carbide and carbon.
And by adopting such a configuration, a phenomenon occurs in which the coating layer has a low coefficient of friction, self-lubricating property, large load resistance and adhesion, and polishes the other sliding surface in contact. Since there is no bobbin, the bobbin moves smoothly in the bobbin case, so that the thread can be smoothly pulled out from the bobbin, and a beautiful seam with excellent appearance quality can be easily formed.

According to a thirteenth aspect of the present invention, the rotary hook device of the sewing machine according to the present invention is characterized in that the point of the outer hook is covered with a coating layer made of carbide and carbon. And, by adopting such a configuration, the coating layer has a low coefficient of friction, self-lubricating property, and a large load resistance, so that a temperature rise due to friction with the yarn can be suppressed, and the cutting of the yarn by the point of the blade Can be prevented.

A fourteenth aspect of the present invention is that the surface of the bobbin case is covered with a coating layer made of carbide and carbon. And
By adopting such a configuration, the coating layer has a low coefficient of friction, self-lubricating property, and large load-carrying capacity. In addition to preventing the inconvenience of cutting yarns, especially chemical fibers that are vulnerable to heat, caused by heat when rotated at high speed, it can also prevent deformation of yarns due to heat and deterioration of properties such as mechanical strength such as tensile strength. So
Stitches such as skips and lanterns can be prevented from being abnormal, and high-quality seams can be held. Furthermore, since the frictional resistance with the thread can be suppressed, the thread smoothly crosses the outer periphery of the bobbin case, so that a beautiful seam can be formed.

A feature of the rotary hook device for a sewing machine according to the present invention according to claim 15 is that the coating layer is formed by PVD. By adopting such a configuration, the coating layer can be formed efficiently and reliably, and the processing temperature when forming the coating layer can be performed at a low temperature of about 250 ° C. It hardly affects the hardness of the base material covered by the layer.

According to a sixteenth aspect of the present invention, the rotary hook device of the sewing machine according to the present invention is characterized in that the coating layer has a layered film structure and that the carbide-rich layer and the carbon-rich layer are alternately arranged. is there. And, by employing such a configuration, the carbide-rich layer can absorb a load, so that a large load resistance can be easily obtained.

A feature of the rotary hook device for a sewing machine according to the present invention according to claim 17 is that the coating layer has a thickness of 0.5 to 10.0 μm. By adopting such a configuration, it is possible to obtain the most preferable thickness necessary for maintaining a stable function without lubrication for a long period of time.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings.

1 to 4 show an embodiment of a rotary hook device of a sewing machine according to the present invention. FIG. 1 is a plan view of a main part, FIG. 2 is a longitudinal sectional view of FIG. 1, and FIG. FIG. 4 is an exploded perspective view illustrating an attached state of the hook retainer, FIG. 4 is a partially enlarged longitudinal sectional view showing, in an enlarged manner, a portion where the rail of the inner hook is fitted into the rail groove of the outer hook, FIG.
Is a partially enlarged longitudinal sectional view of the bobbin, and FIG. 6 is an enlarged longitudinal sectional view of the inner hook retainer.

The rotary hook device of the sewing machine according to the present embodiment is used for an industrial sewing machine that rotates at a high speed.

As shown in FIGS. 1 to 3, the rotary hook device 1 of the sewing machine according to the present embodiment is fixed to one end of a lower shaft, and by operating a sewing machine (not shown), a direction indicated by an arrow in FIG. Has an outer shuttle 3 which is driven to rotate at a high speed of up to 10,000 rpm, and an inner shuttle 4 is housed in the outer shuttle 3. The inner hook 4 is fixed to a sewing machine body (not shown) when the outer hook 3 rotates, and is fitted into a recess 5 formed in the inner hook 4 by a hook stopper 6 partially shown by an imaginary line in FIG. Rotation is prevented. A detachable bobbin case 7 is attached to the inner hook 4. The bobbin case 7 accommodates a detachable bobbin 8 around which a bobbin thread (not shown) is wound. Has become. That is, the bobbin 8 is stored in the inner hook 4. Further, an inner hook retainer 9 (FIG. 3) for holding the inner hook 4 on the outer hook 3 is attached to the outer hook 3 in order to prevent the inner hook 4 from dropping from the outer hook 3. This inner hook retainer 9
Is integrated with the outer hook 3 in an assembled state, and forms a part of the outer hook 3.

As shown in FIG. 4, a track groove 10 for contacting the inner hook 2 is formed on the inner peripheral surface of the outer wall of the outer hook 3, and the inner groove 2 shown in FIG. The rail 11 of the outer hook 3 formed on the outer peripheral surface of the peripheral wall of the inner wall 4 enters and fits.

The outer pot 3 of the present embodiment is made of a suitable steel material such as a chromium molybdenum steel material or a stainless steel material, and is formed into a predetermined shape by performing a suitable cutting process and the like. PVD (Ph
As shown in FIG. 4, at least the surface of the rail groove 10, which forms the sliding surface, of the outer hook 3 has a hardness of Hv100 made of carbide and carbon.
It is formed by covering with about 0 covering layer 12. The coating layer 12 only needs to be formed at least on a sliding surface with another member represented by the rail groove 10. In the present embodiment, the coating layer 12 made of carbide and carbon is also formed on the surface of the blade point 15 that catches the loop of the upper thread (needle thread) of the outer hook 3.

The outer pot 3 may be made of a material lighter than steel, for example, aluminum, titanium, or carbon. With such a configuration, the outer hook 3 can be easily reduced in weight, the stress on the sliding surface is reduced, and more excellent durability without lubrication can be obtained.

When aluminum or aluminum alloy is used as the material for the outer pot 3, the surface is covered with an intermediate film of hard chromium or nickel alloy,
The configuration in which the coating layer 12 is formed makes it possible to reduce the weight of the outer pot 3 and to strengthen the surface of aluminum or an aluminum alloy as a base material to prevent the outer pot 3 from being damaged. This is preferable in that it can be performed.

When chromium is used as the intermediate film, the thickness of the intermediate film is about 1 to 10 μm, preferably about 2 to 6 μm, and most preferably about 2 to 4 μm. When the thickness is smaller than this range, the effect of strengthening the surface of the base material tends to be small, and when the thickness is large, the material tends to be easily peeled. Thus, the thickness of the intermediate film made of chromium is 2
By setting the thickness to about 4 μm, the most preferable thickness required to prevent the outer pot 3 from being damaged can be obtained.

When a nickel alloy is used as the intermediate film, the thickness of the intermediate film is about 1 to 15 μm, preferably about 5 to 12 μm, and most preferably 7 to 10 μm.
m. When the thickness is smaller than this range, the effect of strengthening the surface of the base material tends to be small, and when the thickness is large, the material tends to be easily peeled. As described above, by setting the thickness of the intermediate film made of the nickel alloy to about 7 to 10 μm, the most preferable thickness necessary for preventing the outer pot 3 from being damaged can be obtained. Further, as the nickel alloy, nickel phosphorus (Ni-P), nickel boron, or the like can be used. Furthermore, it is preferable that the intermediate film made of a nickel alloy be formed on the surface of the base material by chemical plating, that is, electroless plating, in order to obtain a dense and uniform film thickness with almost no pinholes.

The inner pot 4 of this embodiment is made of a suitable steel material such as chromium molybdenum steel, stainless steel, or the like, and is appropriately cut to form a predetermined shape. After being mounted and injection-molded using an injection molding machine, as shown in FIG.
1 is coated by a resin layer 13 of a polyimide resin. The resin layer 13 may be formed at least on the sliding surface of another member represented by the rail 11.

The bobbin case 7 of the present embodiment is made of a suitable steel material such as chromium molybdenum steel material or stainless steel material, and is formed into a predetermined shape by performing an appropriate cutting process and the like, similarly to the outer pot 3. Method, ion plating,
The bobbin case 7 is formed by coating the surface of the bobbin case 7 with a coating layer 12 made of carbide and carbon and having a hardness of about Hv1000 by PVD such as sputtering. The coating layer 12 formed on the bobbin case 7 is formed on at least an outer peripheral surface and an inner peripheral surface of the bobbin case 7, more specifically, on a sliding surface such as a region where the yarn contacts and a support portion, and further a region where the bobbin 8 contacts. It should just be done.

The bobbin 8 of this embodiment is made of a suitable steel material such as a chromium molybdenum steel material or a stainless steel material in the same manner as the outer pot 3, and is formed into a predetermined shape by performing an appropriate cutting process and the like. As shown in FIG. 5, the bobbin 8 is formed by PVD such as, ion plating, and sputtering.
Hardness made of carbide and carbon is Hv10
It is formed by coating with a coating layer 12 of about 00. The coating layer 12 formed on the bobbin 8
At least on the outer peripheral surface, more specifically, on a sliding surface such as a region where the bobbin thread contacts, a region supported by the inner shuttle 4, and a region where the bobbin case 7 contacts.

The inner hook retainer 9 which forms a part of the outer hook 3 of the present embodiment is made of an appropriate steel material such as a chromium molybdenum steel material or a stainless steel material similarly to the outer hook 3, and is subjected to an appropriate cutting process or the like. After being formed into a predetermined shape by PVD such as vapor deposition, ion plating, and sputtering, FIG.
As shown in FIG. 2, the surface of the inner hook retainer 9 is formed by coating the surface of the inner hook retainer 9 with a coating layer 12 made of carbide and carbon and having a hardness of about Hv1000. The coating layer 12 formed on the inner hook retainer 9 may be formed on at least a sliding surface, specifically, a sliding surface such as a portion where the yarn contacts and a portion that contacts the inner hook 4.

The method for forming the coating layer 12 is PVD.
Can efficiently and surely form the coating layer 12, and set the processing temperature when forming the coating layer 12 to 250 ° C.
Since it can be carried out at such a low temperature, it is preferable in that it hardly affects the base material coated with the coating layer 12 such as a decrease in hardness.

The thickness of the coating layer 12 is 0.5
The thickness is about 10 to 10 μm, preferably about 0.5 to 5 μm, and most preferably about 0.5 to 4.0 μm. When the thickness is smaller than this range, almost no effect can be obtained, and when the thickness is larger, the adhesiveness tends to decrease. Thus, by setting the film thickness of the coating layer 12 to about 0.5 to 4.0 μm, it is possible to obtain the most preferable thickness necessary for maintaining a stable function without lubrication for a long time. .

Further, the film structure of the coating layer 12 may be a layered film structure, and the carbide-rich layer and the carbon-rich layer may be alternately arranged in a direction perpendicular to the film thickness direction. This is preferable in that a function of absorbing the load by the rich layer can be exhibited to easily obtain a large load resistance. In addition, when the outer hook 3 is rotated at a high speed, an impact load is rarely generated. However, the impact load can be reduced by the load resistance of the carbide rich layer. That is, since the carbide-rich layer can absorb a load, a large load resistance can be easily obtained.

As a material of the resin layer 13, the addition of an additive to the polyimide resin makes the characteristics of the resin layer 13 such as abrasion resistance and mechanical strength sufficient for use as the rotary hook device 1 of a sewing machine. It is preferable in that it can be formed to withstand. Examples of this additive include fillers such as fiber reinforcing materials, fluorocarbon resins, graphite, calcium carbonate, mica, glass beads, dihydrated molybdenum, clay, silica, alumina, talc, diatomaceous earth, hydrated alumina, and shirasu balloon, and lubricants. Various compounding agents such as a release agent, a stabilizer, a colorant, a crystal nucleating agent, a softener and a plasticizer can be used alone or in combination as needed. Furthermore, the addition of at least one of carbon fiber, graphite, molybdenum disulfide, and a fluororesin as an additive can easily improve the self-lubricating property of the resin layer 13 and lower the friction coefficient. This is preferable in that respect.

The resin layer 13 may contain about 1 to 30% by weight, preferably about 1 to 10% by weight, and most preferably 1 to 3% by weight of a lubricant.
This is preferable in that the self-lubricating property can be improved, the friction coefficient can be reduced, and the sliding friction can be easily reduced.

As the lubricant, silicone oil,
Examples include perfluoroether oil and phenyl ether oil.

Since the polyimide resin constituting the resin layer 13 can be injection-molded, a component having a complicated shape can be easily formed by injection molding this polyimide resin.

Next, the operation of the present embodiment having the above-described configuration will be described.

In the rotary hook device 1 of the sewing machine of this embodiment, a coating layer 12 made of carbide and carbon is integrally formed on the surface of the track groove 10 of the outer hook 3.
Has a low coefficient of friction of about 0.1, a self-lubricating property, a large load resistance, and a large adhesion of about 4000 MPa (for example, the adhesion of TiN which is a hard film is 3300).
(Approximately MPa), and there is no phenomenon that the other sliding surface that comes into contact is polished. Therefore, when rotating at a high speed, the coating layer 12 hardly peels off, and can be lubricated for a long time without lubrication. High-speed rotation can be easily and reliably performed.

The rotary hook device 1 of the sewing machine according to the present embodiment
The resin layer 13 made of a polyimide resin is integrally formed on the surface of the rail 11 of the inner pot 4.
No. 3 has a melting point of 380 ° C and a heat deformation temperature of about 340 ° C (AS
TM D648 18.6 kgf / cm ² ), which is extremely high, and is generated on the contact surface as a sliding portion between the rail 11 of the inner hook 4 and the rail groove 10 of the outer hook 3 when the outer hook 3 rotates at a high speed of about 10000 rpm. And the rail 11 of the inner pot 4 and the groove 10 of the outer pot 3
Therefore, the deformation of the contact surface serving as a sliding portion can be reliably prevented.

The rotary hook device 1 of the sewing machine according to the present embodiment
The results of investigating the durability time until the backlash between the rail groove 10 and the rail 11 becomes 0.2 mm when the rotation speed of the outer pot 3 is set to 6000 rpm without lubrication are shown. Shown in comparison with layers. In addition, the product 1 of the present invention in FIG. 7 has a combination of a coating layer 12 on the surface of the rail groove 10 and a resin layer 13 on the surface of the rail 10 (FIG. 7 shows WC / C + PI
The present invention product 2 has a track groove 10 and a rail 11
Are combined with the covering layer 12 (FIG. 7 shows WC
/ C + WC / W), and the conventional product 1 has a combination of steel materials on both surfaces of the rail groove 10 and the rail 11 (FIG. 7).
The conventional product 2 shows a combination of polyimide (the surface of the rail groove 10 is DLC and the surface of the rail 11 is the same as that of the resin layer 13 and is denoted by DLC + PI in FIG. 7).

As is clear from the test results, it was confirmed that the rotary hook device 1 of the sewing machine according to the present embodiment has better durability than the conventional one. That is, as shown in FIG. 7, the conventional products both have a durable time of less than 150 hours, while the products 1 and 2 of the present invention both have a durable time of about 200 hours. The durability time of No. 2 is 1.3 times or more as compared with the conventional product.

The rotary hook device 1 of the sewing machine according to the present embodiment
According to the outer pot 3, the coating layer 12 made of carbide and carbon is integrally formed on the surface of the blade point 15,
Heat generation due to contact between the sword 15 and the thread can be reduced. That is, by forming the coating layer 12 having a low coefficient of friction, self-lubricating property, and large load resistance on the surface of the tip 15, the temperature rise due to friction with the thread can be suppressed, and the cutting of the thread by the tip 15 can be prevented. Can be prevented.

Further, the rotary hook device 1 of the sewing machine according to the present embodiment.
According to the bobbin case 7, the coating layer 1 of the bobbin case 7
No. 2 has a low coefficient of friction, self-lubricating property, large load bearing capacity and adhesion, and does not cause the phenomenon of polishing the other sliding surface with which it comes into contact. It is possible to suppress the occurrence of the inconvenience of cutting the thread, especially the chemical fiber which is weak to heat, by heat when the sewing machine is rotated at high speed for a long time,
Since it is possible to prevent deformation of the yarn due to heat and deterioration of properties such as mechanical strength such as tensile strength, it is possible to prevent stitches such as skipping and lanterns from being abnormal and to maintain high-quality seams. Further, the frictional resistance with the thread can be suppressed, and the thread smoothly passes over the outer periphery of the bobbin case, so that a beautiful seam can be formed.

Further, the rotary hook device 1 of the sewing machine according to the present embodiment.
According to the bobbin 8, the coating layer 12 of the bobbin 8 has a low coefficient of friction, a self-lubricating property, a large load-carrying capacity and an adhesive property, and a phenomenon occurs in which the other sliding surface that comes into contact is polished. Therefore, stable functions can be maintained without lubrication for a long period of time. That is, bobbin 8
Moves smoothly in the bobbin case 7, so that the bobbin 8
The thread can be smoothly pulled out from the thread, and a beautiful seam with excellent appearance quality can be easily formed.

In addition, the rotary hook device 1 of the sewing machine according to the present embodiment.
According to the inner hook retainer 9 which constitutes a part of the outer hook 3, the coating layer 12 of the inner hook retainer 9 has a low coefficient of friction, self-lubricating property, large load resistance and adhesion, and is in contact with the inner pot retainer 9. Since the phenomenon of polishing the other sliding surface does not occur,
A stable function can be maintained without lubrication for a long time.

Further, the rotary hook device 1 of the sewing machine according to the present embodiment.
Table 1 and Figure 2 show the results of an investigation of the relationship between the temperature change (rising temperature) of the outer hook and the bobbin case and the rotation time when the rotary speed of the outer hook 3 was set to 8000 rpm without lubrication, and the standard product. FIG. The products 1, 2 and 3 of the present invention in Table 1 and FIG.
5. The surface of the bobbin case 7 and the surface of the bobbin 8
In 2, the surface of the rail 10 of the inner pot 4 shows the same component in which the resin layer 13 is combined, and the standard product shows a combination of steel materials in both the rail groove and the rail.

[0057]

[Table 1]

As is clear from the test results, it was confirmed that the rotary hook device 1 of the sewing machine according to the present embodiment can reduce the temperature change (temperature rise: exothermic temperature) as compared with the related art. That is, as shown in Table 1 and FIG.
The temperature rise, which is the temperature change of the surface of the outer kettles 2 and 3, is about 8 to 10 ° C. lower than that of the standard product, and the surface temperature of the bobbin case 7 of the products 1, 2, and 3 of the present invention is shown. The changing temperature rise shows a value that is lower by about 1 to 3 ° C. than the standard product.

Therefore, according to the rotary hook device 1 of the sewing machine of the present embodiment, the temperature rise due to the friction between the blade 15 and the thread can be suppressed, so that the cutting of the thread by the blade 15 can be prevented. Since the temperature rise due to the friction between the bobbin case 7 and the yarn can be suppressed, it is possible to prevent the inconvenience of cutting the yarn, especially the chemical fiber which is weak to heat, due to heat when the sewing machine is operated at high speed for a long time. As well as preventing deformation of the thread due to heat and deterioration of mechanical strength such as tensile strength, preventing stitches such as skipping and lanterns, and maintaining high quality seams. it can. Furthermore, since the frictional resistance between the bobbin case 7 and the thread can be suppressed, the thread smoothly passes over the outer periphery of the bobbin case 7, so that a beautiful seam can be formed.

The rotary hook device 1 of the sewing machine according to the present embodiment
According to the method, since the heat generation temperature can be reduced, the rail 1
The deformation of the contact surface serving as a sliding portion between the rail 1 and the rail groove 10 of the outer hook 3 can be more reliably prevented, and the volatilization of the lubricant contained in the polyimide resin constituting the resin layer 13 due to heat is prevented. The lubricating oil can be stably spread over the surface of the resin layer 13 over a long period of time by preventing the blinding phenomenon of the sliding surface of the resin layer 13. Self-lubricating properties can be reliably maintained over a long period of time.

Therefore, according to the rotary hook device 1 of the sewing machine of the present embodiment, it is possible to easily and reliably perform high-speed rotation without lubrication for a long period of time.

The rotary hook device 1 of the sewing machine may have a configuration in which the surface of the rail 11 of the inner hook 4 is a coating layer 12.

Further, as the structure of the rotary hook device 1 of the sewing machine, since the polyimide resin forming the resin layer 13 can be injection-molded, the entire inner hook 4 having a complicated shape formed by injection-molding this resin is used. By adopting such a configuration, it is possible to perform high-speed rotation without lubrication for a long period of time as in the above-described embodiment, and to reduce the weight and weight of the inner hook 4. The inertia force when the outer shuttle 3 rotates can be reduced, and the upper thread can be more smoothly pulled out.

Further, as a configuration of the rotary hook device 1 of the sewing machine, the outer hook 3 is made of a resin layer 1 made of a polyimide resin.
3, and with such a configuration, as in the above-described embodiment, high-speed rotation can be performed without lubrication for a long period of time, and the weight of the outer hook 3 is reduced by using a steel material as a material. Can be reduced to about 1/4 of the case, so that the weight of the outer hook 3 can be easily reduced, the stress on the sliding surface is reduced, and more excellent durability without lubrication is achieved. Obtainable. In this case, it is important that the surface of the rail 11 of the inner pot 4 be the coating layer 12. In other words, any configuration may be used as long as one of the sliding surfaces is covered with a coating layer 12 made of carbide and carbon, and the other is covered with a resin layer 13 made of a polyimide resin.

When the outer pot 3 is made of a polyimide resin, it is difficult at present to form the inner pot holder 9 of a polyimide resin because of problems such as strength. The inner hook retainer 9 may be formed of a polyimide resin.

The present invention is not limited to the above embodiment, but can be modified as required.

[0067]

As described above, according to the rotary hook device of the sewing machine according to the first aspect of the present invention, the sliding surface formed by the coating layer has a low coefficient of friction, a self-lubricating property, and a large load resistance. In addition, the present invention has an extremely excellent effect that it has an adhesive property and does not cause the phenomenon of polishing the other sliding surface with which it comes into contact. Furthermore, since the sliding surface formed of the resin layer has excellent heat resistance, it is possible to prevent thermal deformation due to heat generated by sliding resistance. And so on. Therefore, an extremely excellent effect such as high-speed rotation without lubrication for a long period of time is exhibited.

According to the rotary hook device of the sewing machine according to the second aspect of the present invention, it is possible to easily obtain excellent durability without lubrication on the sliding surfaces of the inner hook and the outer hook that come into contact with each other. In addition, since the outer hook can be easily reduced in weight, the stress on the sliding surface can be reduced, and an extremely excellent effect such as a further excellent durability without lubrication can be obtained.

Further, according to the rotary hook device of the sewing machine of the present invention according to the third aspect, an extremely excellent effect such as the abrasion resistance and mechanical strength of the resin layer can be easily improved.

Further, according to the rotary hook device of the sewing machine of the present invention according to the fourth aspect, it is possible to obtain extremely excellent effects such that the self-lubricating property of the resin layer can be improved and the friction coefficient can be easily reduced. .

Further, according to the rotary hook device of the sewing machine according to the fifth aspect of the present invention, an extremely excellent effect is obtained such that the self-lubricating property of the resin layer can be improved and the friction coefficient can be easily reduced.

Further, according to the rotary hook device of the sewing machine of the present invention according to claim 6, the sliding surface formed by the coating layer is:
It has a low coefficient of friction, self-lubricating property, large load resistance and adhesion, and does not cause the phenomenon of polishing the other sliding surface that comes into contact. It has extremely excellent effects such as the ability to produce

According to the rotary hook device of the sewing machine according to the present invention, the outer hook can be easily reduced in weight, the stress on the sliding surface can be reduced, and the oil-free lubrication can be further improved. Extremely excellent effects such as high durability can be obtained.

According to the rotary hook device of the sewing machine according to the present invention, the outer hook can be reduced in weight and the surface of the base material can be strengthened to prevent the outer hook from being damaged. It has an extremely excellent effect that it can be performed.

Further, according to the rotary hook device of the sewing machine according to the ninth aspect of the present invention, an extremely excellent effect is obtained such that the outer hook can be more reliably prevented from being damaged.

According to the rotary hook device of the sewing machine of the present invention, the outer hook can be reduced in weight and the surface of the base is strengthened to prevent the outer hook from being damaged. It has an extremely excellent effect, such as being able to do so.

Further, according to the rotary hook device of the sewing machine of the present invention according to the eleventh aspect, an extremely excellent effect is obtained such that the outer hook can be more reliably prevented from being damaged.

Further, according to the rotary hook device of the sewing machine of the present invention, the coating layer has a low coefficient of friction, self-lubricating property, large load resistance and adhesion, and has the other contacting property. Since the phenomenon of polishing the sliding surface does not occur, the bobbin moves smoothly in the bobbin case, so that the thread can be pulled out smoothly from the bobbin, and beautiful seams with excellent appearance quality can be easily formed. It has an extremely excellent effect that it can be performed.

Further, according to the rotary hook device of the sewing machine of the present invention, the coating layer has a low coefficient of friction, self-lubricating property, and large load resistance, so that the temperature rise due to friction with the yarn can be prevented. An extremely excellent effect such as being able to suppress the cutting of the thread by the point of the sword is achieved.

Further, according to the rotary hook device of the sewing machine of the present invention, since the coating layer has a low coefficient of friction, self-lubricating property, and large load resistance, the temperature rise due to friction with the yarn is prevented. Because it can be suppressed, it is possible to prevent the inconvenience of cutting yarns, especially chemical fibers that are vulnerable to heat, due to heat when the sewing machine is rotated at high speed for a long time. Since the characteristics such as mechanical strength can be prevented from lowering, stitches such as skipping and lanterns can be prevented, and a very high-quality seam can be held. Furthermore, since the frictional resistance with the thread can be suppressed, the thread smoothly crosses the outer periphery of the bobbin case, so that a very excellent effect such as formation of a beautiful seam can be obtained.

According to the rotary hook device of the sewing machine of the present invention, the coating layer can be efficiently and reliably formed, and the processing temperature for forming the coating layer is about 250 ° C. Since it can be carried out at a low temperature, an extremely excellent effect such as hardly affecting the hardness of the base material coated with the coating layer is exerted.

Further, according to the rotary hook device of the sewing machine of the present invention, since the carbide rich layer can absorb the load, a large load resistance can be easily obtained. It has an extremely excellent effect.

According to the rotary hook device of the sewing machine of the present invention, it is possible to obtain the most preferable thickness necessary for maintaining a stable function without lubrication for a long period of time. It has an extremely excellent effect.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of an embodiment of a rotary hook device of a sewing machine according to the present invention.

FIG. 2 is a longitudinal sectional view of FIG.

FIG. 3 is an exploded perspective view illustrating an attached state of the inner hook retainer of FIG. 1;

FIG. 4 is a partially enlarged longitudinal sectional view showing, in an enlarged manner, a portion in which the rail of the inner pot of FIG. 1 is fitted into the rail groove of the outer pot;

FIG. 5 is a partially enlarged longitudinal sectional view of the bobbin of FIG. 1;

FIG. 6 is an enlarged vertical sectional view of the inner hook retainer shown in FIG. 1;

FIG. 7 is a diagram showing a durable time of the rotary hook device of the sewing machine according to the present invention in comparison with a conventional product.

FIG. 8 is a diagram showing the relationship between the heat generation temperature and time of the shuttle and the bobbin case of the rotary hook device of the sewing machine according to the present invention in comparison with a conventional product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotating hook device of sewing machine 3 Outer hook 4 Inner hook 8 Bobbin 9 Inner hook holder 10 Rail groove 11 Rail 12 Coating layer 13 Resin layer 15 Sword point

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Koji Kikuya, inventor Koji Kikuryo-cho, Chofu-shi, Tokyo 1-2-2 Juku Corporation F-term (reference) 3B150 AA02 CB03 CD04 CE26 DG03 GB03 GB08 HA05 HA12 QA04

Claims (17)

[Claims] 1. A rotary hook device of a sewing machine having an inner shuttle capable of storing a bobbin and an outer shuttle capable of storing the inner shuttle, wherein at least one of the sliding surfaces of the inner shuttle and the outer shuttle is provided with a car. A rotary hook device for a sewing machine, comprising: a coating layer made of bite / carbon; and a resin layer made of a polyimide resin on the other side. 2. The rotary hook device of a sewing machine according to claim 1, wherein the sliding surface of the inner hook is formed by the coating layer, and the outer hook is formed by a resin layer made of a polyimide resin. . 3. The rotary hook device for a sewing machine according to claim 1, wherein the resin layer contains an additive. 4. The method according to claim 1, wherein the additive is carbon fiber, graphite,
The rotary hook device of a sewing machine according to claim 3, wherein the rotary hook device contains at least one of molybdenum disulfide and a fluororesin. 5. The resin layer according to claim 1, wherein said resin layer contains 1 to 30% by weight of a lubricant.
The rotary hook device for a sewing machine according to any one of claims 1 to 7. 6. A rotary hook device of a sewing machine having an inner hook capable of accommodating a bobbin and an outer shuttle capable of accommodating the inner hook, wherein at least a sliding surface of the inner shuttle and the outer shuttle is provided with a carbide tool. A rotary hook device for a sewing machine, wherein the rotary hook device is coated with a coating layer made of carbon. 7. The rotary hook device for a sewing machine according to claim 1, wherein the outer hook is formed in a predetermined shape from a material lighter than steel. 8. The method according to claim 1, wherein the outer pot is formed by covering a surface of a base formed into a predetermined shape with aluminum or an aluminum alloy with an intermediate film made of chromium. The rotary hook device of the sewing machine described in the above. 9. The rotary hook apparatus according to claim 8, wherein the intermediate film has a thickness of 1 to 10 μm. 10. The outer pot is formed by covering a surface of a substrate formed into a predetermined shape with aluminum or an aluminum alloy with an intermediate film made of a nickel alloy. 4. The rotary hook device for a sewing machine according to claim 1. 11. The rotary hook device according to claim 8, wherein the intermediate film has a thickness of 1 to 15 μm. 12. A rotary hook device of a sewing machine having an inner hook having a bobbin case capable of storing a bobbin and an outer hook capable of storing the inner hook, wherein at least the outer peripheral surface of the bobbin is made of carbide carbon. A rotary hook device for a sewing machine, wherein the rotary hook device is covered with a coating layer comprising: 13. A rotary hook device of a sewing machine having an inner hook capable of storing a bobbin and an outer hook capable of storing the inner hook, wherein the point of the outer hook is covered with a coating layer made of carbide and carbon. A rotary hook device for a sewing machine, comprising: 14. A rotary hook device of a sewing machine having an inner hook having a bobbin case capable of storing a bobbin and an outer hook capable of storing the inner hook, wherein the surface of the bobbin case is made of carbide carbon. A rotary hook device for a sewing machine, which is covered with a coating layer. 15. The rotary hook device for a sewing machine according to claim 1, wherein the coating layer is formed by PVD. 16. The method according to claim 1, wherein the coating layer has a layered film structure, and the carbide-rich layers and the carbon-rich layers are alternately arranged. A rotary hook device for a sewing machine according to item 13. 17. The coating layer has a thickness of 0.5 to 10.0.
17. The micrometer according to claim 1, wherein:
The rotary hook device for a sewing machine according to any one of claims 1 to 7.